REMAINING (number with state)Abdomen, S2, hair fringe on rim Present and THICK, mostly or completely obscuring the rim beneath (26) Present but THIN, rim no more than 50% obscured (16) Absent, rim clearly visible, with only a few LIGHT hairs present (11) Absent, rim clearly visible, with only a few BLACK hairs present (2)Abdomen, S3, hairs in center of apical 1/3 of segment - Set just back from the apical fringe hairs Noticeably more ERECT than fringe hairs - If there is a fringe - These erect hairs may be long or short, dense or sparse (30) NOT erect, inclined as much or nearly as much as fringe hairs, tending to be shorter or no longer than the fringe hairs (20) BARE, lacking hair (8)Abdomen, T6, center of segment covered in short, dense, appressed, light colored hair No (32) Yes (13)Abdomen, T6, outline of prominent parallel median ridge Distinctly notched or dipped in center (34) More or less rounded (13) Highly irregular and jagged (12)Abdomen, T6, the true rim which is recessed and hidden beneath the extremely large, prominent projecting flange, when you see this flange you will think you are looking at the rim of the segment but do not be fooled - Note that this means that you need to turn the specimen upside down in order to see the real rim of T6 Rim with either 2 median, 2 lateral, or both set of SMALL triangular teeth, be careful as these teeth are often partially hidden by hairs and can be hard to see (8) Rim smooth without any projecting teeth or angles (4)Abdomen, upper side, hair color and presence or absence of hair bands 1. Most commonly occurring state - Majority of hair on tergites LIGHT - T2-T5 WITH latitudinal bands of dense hair along the apical rim or base of the segments, these bands may or may not go completely across the segment - There may or may not be some dark bristles laterally on the tergites (36) 2. T1 or T1 and T2 with extensive, uniform LIGHT hairs - T3-T6 with upper surface covered with dark hair or dark and light hair intermixed - NO distinct hair bands (5) 5. All hair DARK, NO distinct hair bands (2) 3. T1-T2 with DENSE, SHORT, yellowish ORANGE hair - T3-T5 WITH latitudinal light colored bands of hair along the rim -T6 with long, dark, sparse bristles (1) 4. All hair LIGHT, NO distinct hair bands (1)Head, distance between lateral ocelli vs distance from lateral ocelli to the back edge of the head Distance between lateral ocelli LESS (41) Equidistant (13) Distance between lateral ocelli GREATER (4)Head, inner cheek, area adjacent to the hypostomal cavity, hair pattern 1. Thickness of hair growth gradually increasing from middle to inner cheek, or uniform throughout (31) 3. Hair dramatically and abruptly thickened in comparison to hair growth on middle cheek, LACKING a hairless furrow (15) 2. Hair dramatically and abruptly thickened, WITH a distinct, though often very narrow, HAIRLESS FURROW leading from the hypostomal carina to the eye - note that there will be thick patches of hair to either side of the furrow (14)Head, mandible, number of teeth 3 (30) 4 (16)Head, mandible, produced angle, prong, or lobe on lower edge of mandible, just in from the base Present (41) Absent (6)Legs, front basitarsi, shape 1. Unmodified, NOT dilated (26) 3. Dilated to EXCEED the width of the tibia (15) 2. Slightly dilated to roughly EQUAL the width of the tibia (11)Legs, front coxae, reddish/brown stout hairs located at the base of the forecoxal spine Absent (30) Present as a PATCH of multiple short hairs or stout bristles - Look carefully (16) Present as ONE prominent, thick, red bristle present at base of spine, no patch of bristles present (1)Legs, front coxae, spine Well developed, at least somewhat elongated (36) Reduced to low bump-like tubercles, not elongated (8)Legs, front tarsi, color Reddish brown (26) Pale yellow (19)M. apicalis, M. concinna, M. rotundata M. apicalis - T2 and T3 BOTH bearing lateral, oval-shaped patches, these patches take up about one quarter of the lateral distance of the segment and appear to be absent of hairs and pits, however, at extremely high magnifications you will see they are really composed of very dense, minute, fine hairs - Patches best viewed at an angle - T5 with short, slightly thickened, upright dark hairs, these hairs only slightly longer than hairs on T3 - T4, in comparison to M. concinna, these hairs slightly less dense and slightly lighter (1) M. concinna - T2 and T3 without oval-shaped patches - T5 with robust, long, upright dark hairs, these hairs about twice as long as hairs on T3 - T4 (1) M. rotundata - T2 ONLY bearing lateral, oval-shaped patches, these patches take up about one quarter of the lateral distance of the segment and appear to be absent of hairs and pits, however, at extremely high magnifications you will see they are really composed of very dense, minute, fine hairs - T3 has no patches - Patches best viewed at an angle - Hairs on T5 all light colored (1)M. brevis, M. mendica, M. texana M. brevis - T5 with a complete band of white hair along the rim, similar to T2-4 - Front tibiae narrower and PARALLEL sided, about 1.5 times the width of the basitarsi - Median parallel ridge on T6 often lacking a notch in the center and almost always with finger like projections jutting out in the central third to half of the segment (1) M. mendica - T5 with a total absence hair along the rim, unlike T2-4 which have white bands similar to M. brevis and M. texana - Front tibiae indisputably CURVED OUT along its trailing edge, more than 1.5 times the width of the basitarsi, approaching or equaling 2 times at its maximum width - Median parallel ridge on T6 with rugged edges and a distinct notch, only rarely with finger-like projections - The true rim of T6 with the distance between the submedian teeth being EQUAL TO or LESS than the distance between the submedian and lateral teeth (1) M. texana - T5 almost always with some white hair along the rim, hair band may be complete or lacking - Front tibiae indisputably CURVED OUT along its trailing edge, more than 1.5 times the width of the basitarsi, approaching or equaling 2 times at its maximum width - Median parallel ridge on T6 with rugged edges and a distinct notch, only rarely with finger-like projections - The true rim of T6 with the distance between the submedian teeth being GREATER than the distance between the submedian and the lateral teeth (1)M. centuncularis vs M. lapponica M. centuncularis - Head, clypeus, lack a median tubercle - Legs, tarsal claws have the outer tarsal claw much more rounded than the inner claw (1) M. lapponica - Head, clypeus with a prominent median tubercle on apical rim - Leg, tarsal clase, the inner and outer tarsal claws are equally sharp (1)M. exilis vs M. campanulae, front legs, basal tarsal segments 1 and 2, width, shape, and colo M. campanulae - Slightly narrower than the tibia - Underside of the first basal segment only very slightly concave - Color is dark brown to nearly black (1) M. exilis - Wider than the tibia, though sometimes not by much - Undersides strongly concave - Color tends from a light reddish brown to yellowish brown (1)M. gemula, M. melanophaea, M. mucida M. gemula - T7, which is a small segment and only made visible by turning the specimen upside down, has no projecting central spine, but there may be some small bumps present - T6 with small triangular angles projecting from the rim just on either side of the central notch, note that this is the true rim of T6 do not mistake the very prominent flange that sits above it and hides it, you will have to turn the specimen over to see it - Front basitarsi almost entirely dark brown to black, there may be some yellow along the edge - Generally northern and Appalachian in distribution (1) M. melanophaea - T7, which is a small segment and only made visible by turning the specimen upside down, has a prominent and clearly projecting central spine - T6 with very long, almost spine-like projecting finger like lobes projecting from the rim just on either side of the central notch, note that this is the true rim of T6 do not mistake the very prominent flange that sits above it and hides it, you will have to turn the specimen over to see it - Front basitarsi almost entirely yellow - Northern in distribution (1) M. mucida - T7, which is a small segment and only made visible by turning the specimen upside down, has a raised broad, blunt, triangular mound projecting from the center - T6 with small triangular angles projecting from the rim just on either side of the central notch, note that this is the true rim of T6 do not mistake the very prominent flange that sits above it and hides it, you will have to turn the specimen over to see it - Front basitarsi largely yellow - Southern in distribution (1)M. georgica vs others Others - No such spot exists (2) M. georgica - Leg, front leg, first tarsal segment following the basitarsis, inner side, there is a large oval, nearly black spot that takes up much of the segment, basitaris wider than the tibia (1)M. inermis vs M. lapponica M. inermis - Head, mandible, the 2nd tooth much closer to the apical tooth than the inner tooth (1) M. lapponica - Head, mandible, teeth equally spaced (1)M. inermis, M. relativa, M. centuncularis, body length M. centuncularis and M. relativa - 8-10mm (2) M. inermis - 11-15mm (1)M. lapponica vs M. relativa M. lapponica - Wing, the first submarginal cell with vein r shorter than vein Rs of the second submarginal cell (1) M. relativa - Wing, the first submarginal cell with vein r about equal to vein Rs of the second submarginal cell (1)M. melanophaea vs M. mucida M. melanophaea - Sub-median teeth or the rim of T6 elongate, parallel-sided, horn like, note, don t mistake the much more prominent rim-like projection for the real rim that is hidden by it - Apical end of front tibia with a prominent, strongly projecting, wide, very thin plate that emerges from one side of the outer edge and curves back on itself, looks bit like the bent tip of a table knife (1) M. mucida - Sub-median teeth while prominent are triangular, with sharp points, and clearly not parallel-sided and horn like - Apical end of front tibia with a small and short, but clearly visible, pointed spine that emerges from one side of the outer edge (1)M. montivaga vs M. inermis, size and T6 characters M. inermis - 11-15mm in size - The area above the prominent medial ridge on T6 covered with extremely UNCLEAR, shallow pits of varying size (1) M. montivaga - 9-11mm in size - The area above the prominent medial ridge on T6 covered by TINY pits, much smaller than those on T5, pits are closely packed and are CLEAR in outline, even though they may overlap somewhat (1)M. mucida vs M. xylocopoides M. mucida - T6, above the prominent notched ledge, reflects some light between the dense pitting and is overall concave, but uniformly so across the surface - The true rim of T6, which is blocked from dorsal view by the prominent ledge, is very distinctly concave and bounded on its lateral sides by a prominent projecting tooth - In direct comparison, T2 primarily covered with pale golden yellow hair, with perhaps a a very narrow edging of black just along rim, and wings with dark coloration toward the anterior edge and tip, but not as dark and extensive as M. xylocopoides (1) M. xylocopoides - T6, above the prominent notched ledge, reflects almost no light and appears sandpaper like, upon magnification you will see a uniform field of many tiny pits upon which a few pits about 4x the size are scattering, located directly above the notched ledge is a deeply impressed rounded triangular indentation with sharp, clear boundaries about the same width at the base as the notch - The true rim of T6, which is blocked from dorsal view by the prominent projecting ledge, is only slightly concave to almost completely straight across, without any teeth on its lateral sides - In direct comparison, T2 a mix of black and yellow hairs, with perhaps a a very narrow edging of black just along rim and forewings darker (1)M. parallela vs M. townsendiana, abdomen,T6, shape of notch in the prominent median parallel ridge M. parallela - Round, as half or 2/3 of a circle, sides of notch roughly parallel or curved back in towards each other (1) M. townsendiana - Broadly v-shaped, sides of notch inclined away from one another as in a V (1)M. petulans, M. concinna, M. apicalis, M. rotundata, S4, width of its amber, transparent, paper-like rim 2. All others - Narrow, less than the width of the hind basitarsus to apparently absent (4) 1. M. petulans - Super wide, about as wide as the end of the hind tibia (1)M. petulans, M. texana, M. mendica, M. brevis, combination of T6 rim and S5 characters- Careful on the T6 character as this rim is hidden when viewing from above by a prominent parallel ridge 2. All others - T6 rim WITH a small pair of both submedian and lateral teeth - S4 with an only moderately wide amber transparent, paper-like rim (3) 1. M. petulans - T6 LACKING any submedian teeth, lateral teeth - S4 with an exceptionally wide amber, transparent, paper-like rim - T6 below the prominent carinate ridge has a different feel to it than the other species (1)M. pugnata vs M. inimica M. inimica - Front basitarsi LACKING a distinct brush of dense, black, short hair along the inner rim near the base, all hairs in this region about the same golden to slightly rusty color - Scutum and T1 with hair of moderate length (1) M. pugnata - Front basitarsi WITH a distinct brush of dense, black, short hair along the inner rim near the base, these hairs are clearly darker than the other hairs - Scutum and T1 with noticeably long and messy hair (1)M. relativa, M. centuncularis, M. montivaga - Warning, take care, these differences can be variable and therefore quite tricky M. centuncularis - SMALL, 8-9mm - UNIQUE in having the outer and longer tooth on the claws of the hind leg much more rounded over and blunt on the tip than the inner tooth of the claw - Clypeus rim, when viewed end on, with middle 1/3 clearly thickened and slightly extended, this extended area may have some vague small bumps but is usually straight across - On T6, the area above the prominent medial ridge is SHINY, covered with extremely UNCLEAR, shallow pits of varying size (1) M. montivaga, - LARGER, 9-11mm - The outer and longer tooth on the claws of the hind leg the same shape on the tip as that of the inner claw -Clypeus rim, when viewed end on, is slightly thickened across middle 2/3 and may possibly have a small bump in the center - On T6, the area above the prominent medial ridge is somewhat shiny, covered by TINY, closely packed pits, much smaller than those on T5, these pits are CLEAR in outline, even though they may overlap (1) M. relativa - SMALL, 8-10mm - The outer and longer tooth on the claws of the hind leg the same shape on the tip as that of the inner claw - Clypeus rim, when viewed end on, with a small yet stout knob projecting up and out in middle, may have one or more much smaller knobs to either side - On T6, the area above the prominent latitudinal ridge is relatively shiny and is covered by MEDIUM sized pits, moderately dense, and similar in size and density to those on T5, pits are relatively clear in outline and may be touching (1)M. rubi vs M. integrella, abdomen, T7, rim M. integrella - With a very low point in center (1) M. rubi - Rim drawn out to a noticeable point in the center (1)State or province where bee was collected FL (37) NC (36) SC (36) AL (35) GA (35) MS (35) IL (31) NJ (31) PA (31) VA (31) WV (31) DC (30) DE (30) IN (30) MD (30) OH (30) KY (28) TN (28) MI (23) WI (23) NY (22) CT (20) Ontario (20) MA (19) RI (19) ME (18) Quebec (18) NH (17) VT (16) New Brunswick (13) Nova Scotia (12) Prince Edward Island (12) Newfoundland and Labrador (5) SD (3)Subgenus Xanthosarus (8) Megachiloides (7) Megachile (5) Chelostomoides (4) Sayapis (4) Eutricharaea (3) Litomegachile (3) Argyropile (2) Melanosarus (2) Pseudomegachile (2) Acentron (1) Callomegachile (1) Leptorachis (1) Pseudocentron (1)